21554223211 has 16 divisors (see below), whose sum is σ = 23035898880. Its totient is φ = 20096778240.

The previous prime is 21554223191. The next prime is 21554223227. The reversal of 21554223211 is 11232245512.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21554223211 - 2⁵ = 21554223179 is a prime.

It is a super-2 number, since 2×21554223211² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21554223211.

It is not an unprimeable number, because it can be changed into a prime (21554223241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1523691 + ... + 1537771.

It is an arithmetic number, because the mean of its divisors is an integer number (1439743680).

Almost surely, 2^21554223211 is an apocalyptic number.

21554223211 is a deficient number, since it is larger than the sum of its proper divisors (1481675669).

21554223211 is a wasteful number, since it uses less digits than its factorization.

21554223211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14934.

The product of its digits is 4800, while the sum is 28.

Adding to 21554223211 its reverse (11232245512), we get a palindrome (32786468723).

The spelling of 21554223211 in words is "twenty-one billion, five hundred fifty-four million, two hundred twenty-three thousand, two hundred eleven".